Cable Voltage Drop

This calculator determines the voltage in a cable based on the cable size and load current.

Please select the cable type (or wire resistance if known). Sizes in brackets are not an exact match to AWG.

Wire Size2 AWG / 33.6mm3 AWG / 26.7mm4 AWG / 21.2mm5 AWG / 16.8mm6 AWG / 13.3mm7 AWG / 10.5mm8 AWG / 8.37mm9 AWG / 6.63mm10 AWG / 5.26mm11 AWG / 4.17mm12 AWG / 3.31mm13 AWG / 2.62mm14 AWG / 2.08mm15 AWG / 1.65mm16 AWG / 1.31mm17 AWG / 1.04mm (32/0.2)18 AWG / 0.823mm19 AWG / 0.653mm20 AWG / 0.518mm21 AWG / 0.41mm (14/0.2)22 AWG / 0.326mm24 AWG / 0.205mm26 AWG / 0.129mm28 AWG / 0.081mm (7/0.12)30 AWG / 0.051mm

Wire resistance (Ω per 1000m)

Wire length in metres

Current draw in Amps

Total resistance in Ω (each wire)

Voltage drop (each wire)

Wattage waste (each wire)

A wire size chart can be found here.